【FLUTTER ANDROID STUDIO and IOS】Dio Http Cache

 import 'package:dio/dio.dart';

import 'package:dio_http_cache/dio_http_cache.dart';
import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter cache with dio',
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  DioCacheManager _dioCacheManager;
  String _myData;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: ListView(
        children: [
          FlatButton(
            child: Text(
              'getData',
            ),
            onPressed: () async {
              _dioCacheManager = DioCacheManager(CacheConfig());

              Options _cacheOptions =
              buildCacheOptions(Duration(days: 7), forceRefresh: true);
              Dio _dio = Dio();
              _dio.interceptors.add(_dioCacheManager.interceptor);
              Response response = await _dio.get(
                  'https://jsonplaceholder.typicode.com/users',
                  options: _cacheOptions);
              setState(() {
                _myData = response.data.toString();
              });
              print(_myData);
            },
          ),
          FlatButton(
            child: Text(
              'Delete Cache',
            ),
            onPressed: () async {
              if (_dioCacheManager != null) {
                bool res = await _dioCacheManager.deleteByPrimaryKey(
                    'https://jsonplaceholder.typicode.com/users');
                print(res);
              }
            },
          ),
          Text(
            _myData ?? '',

          ),
        ],
      ),
    );
  }
}